Experimental study of diffusion coefficients and assessment of atomic mobilities in FCC Al–Cu–V alloys

With the increasing demand for high-temperature aluminum (Al) alloys, there is a need for fundamental kinetic information to guide their design and development. This study investigates the diffusion behavior of the FCC Al–Cu–V system and assesses the atomic mobility parameters. Diffusion couples were assembled and annealed at 530, 555, and 580 °C for 1500 h to facilitate solute diffusion. The concentration profiles of Cu and V were measured using electron probe microanalysis (EPMA), and the diffusion coefficients were extracted using the Forward Simulation Analysis (FSA) method. The atomic mobility parameters for the Al–Cu–V system were assessed using the diffusion models in the DICTRA software program and verified by validation experiments involving annealing at temperatures of 535 and 565 °C for 1500 h. The activation energies for the diffusion of Cu and V were calculated and analyzed. The results reveal that adding Cu increased the diffusivity of V, while adding V decreased the diffusivity of Cu within the Al–Cu–V system. These findings of the kinetics of the FCC Al–Cu–V system would be beneficial for alloy design and processing optimization.